Electric apparatus for treating emulsions



H. C. EDDY March 24, 1942.

ELECTRIC APPARATUS FOR TREATING EMULSIONS Original Filed Jan. 26, 1937[/v v1v TOR HAROLD C; EDDY ATTORNEK Patented Mar. 24, 1942 ELECTRICAPPARATUS FOR TREATING EMULSIONS Harold C. Eddy, Los Ang eles, Calif),assignor, by

mcsne assignments, to Petrolite Corporation, Ltd., Wilmington, Del., acorporation of Delaware Original application January 26, 1937, SerialNo.

122.470. Divided 1938, Serial No. 218,681

6 Claims.

My invention relates to a novel electric apparatus for treatingemulsions which finds utility in the electric treatment of emulsionsregardless of the manner of forming these emulsions or the particularconstituents thereof. For instance, while the electric treaterherein-disclosed has been found to be very effective in a desaltingprocess such as exemplified in my Patent No. 2,182,145, infra, it isalso generally applicable to the dehydration of crude oil emulsions orother emulsions, and it is an object of the present invention to providea novel apparatus for electrically treating emulsions.

It is a further object of the present invention to provide an electrictreater including an upper and a lower live electrode with anintermediate live electrode structure, the emulsion being introducedthrough a grounded means.

Further objects and adva tages of the present invention will be apparentto those skilled in the art from the following description.

Referring to the drawing:

Fig. 1 is a vertical sectional view of the preferred form of electrictreater.

Fig. 2 is an enlarged fragmentary view of the upper and intermediateelectrode structure.

' Fig. 3 is a sectional view of the emulsifying valve discharging intothe electric field.

In Fig. 1, the emulsion is forced under pressure through a pipe 88leading to the electric treater 81. This pipe is connected to adistributor means I05 disposed in the electric treater 81 and best shownin Figs. 1 and 3.

Referring to Fig. 3, it will be noted that the pipe 86 carries a primarymember I06 which cooperates with a secondary member I01 in forming anannular discharge passage I08. It is often possible to 'movably mountthe secondary member I01 resiliently moving it toward the primary memberI06 so that the size of the annular discharge passage I08 quantity ofthe mixture moving through the pipe 86. In accomplishing this result,the secondary member I01'may be provided with a pin I08a guided in aspider I09 and carrying a spacer H at its lower end. A compressionspring III is disposed between the spider I09 and the spacer H0 andserves to resiliently move the secondary member I01 downward. When noliquid is moving through the pipe 86, the members I and I01 will be incontact, but as soon as a flow is established, the pressure will forcethe secondary member I01 upward a slight distance to open the annulardischarge passage I00 in degree proportional to the quantity of liquidto be discharged.

The details of one type of treater 81 which I have found particularlyadvantageous are best shown in Fig. 1. Referring to this figure, thistreater 81 provides a tank 5 including a top is dependent upon the andthis application July 11,

member 6 and a bottom member II1, this tank being grounded as indicatedby the numeral IIII.

Suspended from insulators H9 is a live electrode means, shown asincluding an upper electrode I20 and a lower live electrode I2I, thelatter being supported from and electrically connected to the upper liveelectrode I20 by rods I22.

Suspended from an insulator I24 and positioned between the upper andlower live electrodes I20 and I2I is an intermediate live electrodestructure I25respectively cooperating with the electrodes I20 and I2I inproviding an upper treating space I26 and a lower treating space I21. Iprefer to form the intermediate electrode structure I52 of twoelectrodes I28 and I29 connected by a support I30.

The electrodes I20, I2I, I28, and I29 are preferably formed ofinterstitial character. A form of construction which I have foundparticularly desirable is illustrated in Figs. 1 and 2. Referring to theelectrode I20, this electrode is shown as including a plurality of innerand outer rings I32 and I33 between which extend rods or pipes I34. PinsI30 depend therefrom and carry a plurality of concentric rings I31, eachof which provides a lower edge I38 adjacent which the electric field isvery concentrated.

The electrode I28 is similarly formed with rods or pipes I40extendingoutward from a support I41 and carryingupward-extending pins which, inturn, mount a plurality of concentric rings I43. The rings I43 arepreferably disaligned from the rings I31 so that the most intenseportion of any electric field established in the treating space I26 isinclined as indicated by dotted lines I44 in Fig. 2. Such anedge-to-edge field is very effective.

The electrode I29 is formed similar to the electrode I28 and providesdownward-extending rings I50. Similarly, the electrode I2I is formedsimilar to the electrode I30 and provides upwardextending rings I5I sothat a field is established in the treating space I21 similar to thatpreviously described in the treating space I26. I have found itpreferable to form the electrodes I2I and I29 of smaller diameter thanthe electrodes I20 and I28.

This type of electrode structure ,presents a minimum impedance togravitational separation in the tank II5,.therings and the supportingmeans therefor covering only a small fraction of the totalcross-sectional area of the tank. Further, the inters'itial nature ofthese electrodes permits free communication between the electric fieldand facilitates rapid removal of coalesced water masses, therefrom.

Various means may be utilized for energizing the electrodes to establishelectric fields in the treating spaces I26 and I21. In the construclivetion illustrated, all of these electrodes are live, the only groundedportions being the tank and the emulsifying distributor means I05, thelatter discharging directly into the treating space I21 to move theemulsion outward therein and suc cessively through the edge-to-edgefields. By proper design of the electrical system, the potential betweenthe intermediate electrode structure I25 and the electrodes I20 and I2Ican be made much higher than the potential between any of the liveelectrodes and ground. In Fig. 1, such a system is shown as includingtwo transformers I60 and IN connected in additive relation. In thisconnection, one terminal of each secondary winding is grounded asindicated by the numeral I62, the high tension terminal of thetransformer IGI being connected by a conductor I 63 to the intermediateelectrode structure I25, and the high tension terminal of thetransformer I50 is connected by a conductor I64 to the upper and lowerlive electrodes I20 and I2I. Suitable of electric dehydration ofemulsions.

Assuming, for instance, that each transformer develops a potential of12,000 volts, the potential across the upper treating space I26 will be24,000 volts, as will also the potential across the lower treating spaceI21. However, the potential between the emulsifying distributor meansI05 and the electrode I29, or the electrode I2I, will be only 12,000volts. Use of such a system tends to prevent short-circuiting to thedistributor means I05 and also permits introduction of the emulsiondirectly into a field of high voltage. I believe it to be new to utilizeupper and lower live electrodes with an intermediate live electrode inthis capacity.

The action of the electric fields is to coalesce the dispersed waterparticles of the emulsion into masses of sufficient size to gravitatefrom the oil. Thus, after the treater has been in operation for aperiod, the upper end of the tank I I5 will contain the treated oil andthe lower end of the tank will contain a body of separated water. Thesebodies will separate at a rather definite surface or level, indicated inFig. 1 by the numeral I10. It is desirable to rather definitely controlthis level to prevent grounding of the electrode I2I. In thisconnection, it will be apparent that an electric field will beestablished in an auxiliary treating space "I between the lower liveelectrode I2I and the body of water in the bottom of the tank II5. Ifthe level I is carried too high, this auxiliary fieldlrnay short out.However, with proper control of the level I10, this auxiliary field canbe utilized to further treat the settling water particles and can beused to break an inverse-phase or reverse-phase emulsion as will behereinafter described.

To control the water level in the tank I I5, I have shown an automaticsystem including a pipe I communicating with the upper part of the tankH5 and a pipe I16 communicating with a water draw-oil. pipe I11 whichopens on the lower end of the tank H5. The pipes I15 and I16 communicatewith a float chamber I18 in which the oil and the water are in surfacecontact at a level corresponding to the level I10. A properly balancedfloat I19 is disposed in the chamber I18, being so formed as to float inwater and sink in oil. The position of this float will thus change inresponse to changes in the level I10. This float may be pivoted on a pinI80 connected to an arm I8I which is connected to a valve I82 in thepipe I11 by any suitable means. such as a link I83 connected to an arm Iof the valve I82 pivoted at I85 and operatively connected to the-stem I86 of this valve. If the water level rises, the valve I82 will thus beopened a further distance to drain additional quantities of water fromthe tank I I5 and thus maintain the water level constant. Various othersystems for controlling the position of this water level may be utilizedwithout departing from the spirit switches and control means-limitingthe current of the present invention.

The treated oil moves from the upper end of the tank II5 throughapipe200, the flow being controlled by a valve 20I which, in turn,assists in controlling the pressure in the tank II5. It is usuallypreferable to introduce the emulsion directly into the electric fieldrather than to introduce the emulsion into the tank II 5 at a pointspaced from the field, allowing the emulsion to gravitate thereinto.Sludging tendencies are almost completely eliminated by a directintroduction into the electric field.

Usually, though not invariably, it is desirable to carry a slightpressure in the electric treater 81, this pressure being fromatmospheric pressure to approximately 50 lbs/sq. in. or above.

This application is a division of my application Serial No. 66,404,filed February 29, 1936, and its continuation-in-part Serial No.122,470, now Patent No. 2,182,145.

Various other changes and modifications can be made without departingfrom the spirit of the present invention as defined by the appendedclaims.

I claim as my invention:

1. In combination in an electric treater includ ing a tank: an upperlive electrode in said tank; a lower live electrode in said tank; anintermediate live electrode structure between said upper and. lower liveelectrodes and cooperating therewith in defining upper and lowertreating spaces; means for impressing a potential difierence betweensaid intermediate electrode structure and said upper and said lower liveelectrodes; introduction means grounded to said tank for discharging afluid to be treated radially into said lower treating space at aposition intermediate the upper and lower ends thereof; and means forinsulating said upper, lower and intermediate electrode structures fromsaid tank and grounded introduction means whereby auxiliary electricfields are set up between said grounded introduction means and the liveelectrodes bounding said lower treating space and between the tank andeach of the electrodes.

2. In combination in an electric treater including a tank: an upper liveelectrode of interstitial character in said tank; a lower live electrodein said tank and providing a central opening; means for electricallyconnecting said lower live electrode to said upper live electrode andfor supporting said electrodes as a unit insulated from said tank; anintermediate live electrode structure of interstitial character betweensaid upper and lower live electrodes; means for supporting saidintermediate live electrode structure in spaced relationship with saidupper and lower liv-e electrodes to form upper and lower treating spacesand for insulating said intermediate live impressing between saidintermediate live electrode structure and said upper live electrode andbetween said intermediate live electrode structure and said lower liveelectrode a potential difand said lower portion ference higher than thepotential difference between said upper, lower, or intermediateelectrode structures and ground; and an emulsiondistributing meansgrounded to said tank and extending upward through said central openingof said lower live electrode and providing an annular orifice fordirecting emulsion radially outward between said lower live electrodeand said intermediate electrode structure.

3. In combination in an electric treater including a tank: an upper liveelectrode of interstitial character in said tank and insulatedtherefrom, said electrode extending horizontally across a substantialportion of the space inside said tank; a lower live electrode insulatedfrom said tank and of substantially smaller size than said upper liveelectrode and disposed below said upper live electrode; an intermediateelectrode structure between said upper and lower live electrodes andproviding an interstitial upper portion spaced below said upper liveelectrode to form an upper treating space and a lower portion spacedabove said lower live electrode to form a lower treating space, saidupper portion being of a size commensurate with that of said upper liveelectrode being of a smaller size commensurate with that of said lowerlive electrode; means for introducing an emulsion into said lowertreating space; and means for establishing electric fields in both saidupper and said lower treating spaces and for maintaining a difference inpotential between said tank and each of said upper and lower liveelectrodes.

4. In combination in anielectric treater includcluding a grounded tank,the upper portion of which provides a space'for oil and water undergoinggravitational separation and the lower portion of which provides a spacefor a body of separated water: an upper live electrode in said upperportion of said tank; means for suspending said upper live electrode insaid upper portion of said tank, said means including insulating meansfor insulating said upper live electrode from said tank; rod meansformed of electrically conducting material, said rod means beingsupported by said insulating means and electrically connected to saidupper live electrode and extending downward to a position below saidupper live electrode; a lower live electrode electrically connected toand supported by said rod means ata position below said upper liveelectrode but above the surface of said body of water whereby said rodmeans electrically connects said lower live electrade to said upper liveelectrode; an intermediate electrode structure; means for supportingsame between said upper and lower electrodes to cooperate therewith indefining upper and lower treating spaces, said supporting meansincluding means for insulating said intermediate electrode structurefrom said tank; means for establishing between said intermediateelectrode structure and said upper and lower live electrodes a potentialdifierence substantially greater than the potential difference betweenany of these electrode structures and the grounded tank therebyestablishing also a field-establishing potential difference between saidlower live electrode and said body of water; and means for deliveringemulsion to said lower treating space.

5. In combination in an electric treater including a grounded tank, theupper portion of which provides a space for oil and water undergoinggravitational separation and the lower portion of which provides a spacefor a body of separated water: an upper live electrode in said upperporof which provides a space spaces and between said tion of said tank,said electrode being of interstitial character and providing an opening;means for suspending said electrode in the upper portion of said tank,said means including insulating means for insulating said electrode fromsaid tank; rod means formed of electrically conducting material, saidrod means being supported by said insulating means and electricallyconnected to said upper live electrode and extending downward to aposition below said upper live electrode; a lower live electrode ofinterstitial character insulated from said tank and providing an openingand electrically connected to and supported by said rod means at aposition below said upper live electrode but above the surface of saidbody of water whereby said rod means electrically connects said lowerlive electrode to said upper live electrode; an intermediate electrodestructure of interstitial character between said upper and lower liveelectrodes and cooperating respectively therewith in defining upper andlower treating spaces; means extending downward through the opening ofsaid upper live electrode for suspending said intermediate electrode inposition; an emulsion distributor means grounded to said tank andextending upward through the opening of said lower live electrode andproviding orifice means discharging into said lower treating space; andmeans for establishing electric fields in said upper and lower treatinglower live electrode and said body of water in the lower end of saidtank.

6.. In combination in an electric treater including a grounded tank theupper portion of which provides a space for 0'1 and water undergoinggravitational separati and the lower portion fora body of separatedwater: an upper live electrode of interstitial character in said tank,said electrode extending horizontally across a substantial portion ofthe space inside said tank and providing a central opening; means forsuspending said electrode in the upper portion of said tank, said meansincluding insulating means for insulating said electrode from said tank;rod means formed of electrically conducting material, said rod meansbeing electrically connected to and extending downward from theperiphery of said upper live electrode and providing inward-extendingportions positioned below said upper live electrode; a lower liveelectrode of substantially smaller size than said upper live electrodeand electrically connected to said inward-extending portions wherebysaid rod means electrically connects said lower live electrode to saidupper live electrode: an intermediate electrode structure between saidupper and lower electrodes and providing an interstitial upper portionspaced below said upper live electrode to form an upper treating spaceand a lower portion spaced above the lower live electrode to form alower treating space, said upper portion being only slightly smaller insize than said upper live electrode to prevent shortcircuiting to saidrod means and said lower portion being of a. size smaller than saidupper portion and of a size commensurate with that of said lower liveelectrode; means extending downward through said opening of said upperlive electrode to support said intermediate electrode; means forintroducing an emulsion into said lower treating space; and means forestablishing electric fields in both said upper and said lower treatingspaces.

HAROLD C. EDDY.

